Professional awards: Leadership in Diversity Award, National Council of Teachers of English, 2009; Outstanding Teaching Award, University of Michigan, 1998.

Publications: "Multicultural Strategies for Education and Social Change; 'Carriers of the Torch' in the U.S. and South Africa," 2006; "African-American Literacies Unleashed; Vernacular English and the Composition Classroom," co-author, 2005; editor, four other books; 15 articles in refereed journals.

By using that particular piece of African-American vernacular, the girl actually meant "he misses the bus all the time," said Dr. Ball, a Stanford University expert in educational linguistics and the inaugural Dr. Barbara A. Sizemore distinguished professor at Duquesne University's School of Education.

Dr. Ball said teachers, especially those in urban schools across the nation, need to start understanding that African-American speech is its own language, with specialized words, grammar and ways of communicating.

"People may think it's all about slang," she said, "but it goes much deeper."

In the case of the roll-call anecdote, when the student said "he be missing the bus, she meant it's a habitual pattern, so when she was corrected by the teacher, she was aware that was not what she had meant to say."

As with any language, she said, "there's a much richer meaning if you can understand the intended colloquial meanings that go with the expressions."

Her years of research on the subject have not been aimed at promoting African-American vernacular at the expense of standard, academic English, but to show how understanding its patterns can enhance communication and teaching.

When she lectures on the topic to English teachers around the country, "they know they're having problems understanding what their students are trying to communicate to them, and when I give them examples of what the student is actually trying to say, it's like a light comes on."

Once teachers learn more about the vernacular, she said, "they can then begin to understand what the students are trying to communicate and how that can be translated into academic English and how that can actually enrich the education they're receiving at school."

The students in turn can then begin to learn the techniques they need, particularly in writing, to communicate clearly to other audiences, she said.

Dr. Ball said some African-American speech patterns can be traced to West African languages, such as dropping certain consonants ("poh" for "poor") or omitting an "s" on a plural word ("she has three room in her house").

Others may have their roots in the experience of slavery, she said.

One common form of expression among African-Americans is "signifying," which she described as making an indirect, often sarcastic comment that seems to have a different surface meaning.

Among black teens, she said, "someone may say, 'I really like those shoes you have on. Where'd you get 'em?' and everyone will start laughing because they may know they came from Kmart or Wal-Mart."

This kind of indirect speech might have developed when slaves wanted to convey one meaning to each other and different one to their owners, she said. "I believe it was [African-American novelist] Richard Wright who said 'We speak our tongue in front of the lords of the land, yet they don't understand exactly what we are saying.' "

The challenge of understanding any student vernacular, she said, is complicated by the fact that new words and phrases crop up so quickly.

"They may take a term like 'cool' and reverse the usage and mean just the opposite, which often happens in youth culture," she said. "By the time the older generation understands what they mean, they've moved on to something new.

"It's a dynamic, ever-changing language, and yet there are consistent underlying grammatical features of African-American vernacular that haven't changed over the years."

For those who complain that the vernacular degrades the standards of English, she said it's important to remember that "American English is different from the English used in Europe, and the language that we have is much richer because of the language of African-American vernacular."

In one teaching experiment she set up, Dr. Ball took topics the students were interested in, such as music and teen pregnancy, and then summarized them in several different styles of writing.

One particular style, called "narrative interspersion," involves inserting comments about the writer's own experience into the article, and that style appealed to the African-American teens more than any other group of students, she said.

While putting personal anecdotes into an essay on ecology, for instance, might not be the typical approach, it could actually enhance learning for all students, she noted, because "sharing experiences through narrative is how we make much more lasting meaning than just listing factual knowledge."

Dr. Ball was hired in part to "weave a new urban education strand throughout the curriculum" of Duquesne's education school, and to enhance the university's links with nearby public schools in the Hill District.

Improving education for teachers heading into urban school systems is essential, she said, and if she ran the world, teachers not only would be paid much more, but good urban teachers would get a hefty differential.

"My goal is for teachers to be more open and inclusive in their acceptance of diverse ways of teaching and learning and expressing ideas, and to be able to take all of their knowledge and think on the spot about what needs to be done to address the needs of these particular students.

"That requires a higher level of preparation for teachers, which requires more innovative thinking, and so I think they should be much higher paid."

In teaching students oral and written communication, the primary goal should be to get them to express their ideas freely and without fear, Dr. Ball said.

When she is working with African-American students on their writing, she said, "what we encourage them to do is to get the beauty of these ideas out on the paper first, and then edit it for their audience."

A key part of that process, she said, is persuading teachers to look at African-American vernacular "not as something wrong, but as a different variety of language."

"It's true that the school's job is to socialize students and take them somewhere academically that will pay off as they continue the journey, but if we never deal with these attitudes toward language, we can never get beyond them."